Fishing with a casting float is extremely popular. With the help of a casting float it is possible to position the fishing-tackle at a relatively great distance from the bank, thus enabling a much greater area to be fished, often in much more favourable places than is the case in conventional float-fishing with a rod. Floats are used essentially with two main types of fishing-tackle, namely in angling where the hook is used with bait and a sinker, and also in the casting of flies or light spinners and similar tackle with the aid of a casting rod or a casting reel.
We are already familiar with a whole range of different types of casting floats. All earlier casting floats nevertheless had two main shortcomings, namely too little clearance between the sinker and the hook and problems in determining the correct depth.
It is a known fact that the fish is frightened when the sinker is too near the hook, and it is noticeable that much more fish is caught as soon as an adequate length of snell is left between the sinker and the hook with its bait. This problem was partly solved by means of the applicant's own U.S. Pat. No. 140,364, in which the float is provided with a hollow extension at the rear end such that a small sinker may be pushed into the bottom of the extension so as to produce a certain amount of clearance between the sinker and the hook. However, this clearance is greatly restricted in practice, since the length of the snell may not be greater than the distance from the hook in the front chamber to the rear edge of said extension. The length to which the snell is restricted in practice is 8-10 cm, and although this is a great improvement in relation to earlier designs of float in which the sinker was immediately adjacent to the hook, a snell of this length is still not ideal.
A stop is commonly attached to the line in such a way that, once the casting float has been cast, the hook and the sinker will leave the chamber in the float and will sink downwards towards the bottom until the stop makes contact with the rear end of the float. When finding the correct depth, however, one must work forward laboriously by trial and error in an effort to find the depth at the point at which the float is being cast, and then attaching the stop in such a way as to give the hook adequate clearance from the bottom. During these trials there is of course a great risk of the hook getting fast on the bottom.
The problems referred to above are associated with the use of the casting float in connection with so-called angling. When using the casting float in connection with fly-fishing and light spinning, etc., the problem has been to wind the snell on the float in such a way that it is firmly attached to the float during the cast, but that it will unwind as soon as the float hits the water. Various solutions have been proposed, for example in accordance with Norwegian Pat. No. 98285, in which the float is fitted with an axially sliding front part which is pushed into contact with the upper part of the float during the cast, thus holding the snell in place, and where the front part of the assembly will be pushed forwards to release the line when the float hits the water. Other solutions have also been proposed in which the fly or flies are attached by means of a fairly weak permanent magnet and in which the flies are released from the magnets by inertia as the float hits the water.